Mounting alloy dies



Dec. 24. 1935. w A) WISSLER MOUNTING ALLOY DIES Filed Sept. 23, 1951 IN VEN TOR:

ATTO" EYS.

Patented Dec. 24, 1935 UNITED STATES PATENT OFFICE The invention relates to a metho dies, and has par for extremely har wire drawin or less brittle alloys, the die by mounting The suppor only serves to reinforce the metal than the and shaped into any ratus in which the die is to be used. Heretofore ting has consisted in shrinking on an outasting a metal such as bronze around the die in not entirely metal.

the usual manner of moun pressing the die into a ring,

side casing,

of this sort they do not die from cracking un cially under which will per cracking under ing operation, certain alloys as tirely unsatisfactory mounted in the usual manner,

tion of Indiana Application September 2 desired or c the shape are ticular reference to a d alloy dies 3 Claims.

(1 of mounting mounting of the type used in metal not size to suit the appadesired. Mountings satisfactory, since give suiiicient support to prevent the der normal usage, and espeany severe strain. It is an object of my invention to provide a more eflicient manner for mounting alloy dies,

dies which ency to crack.

In accordance is formed about the mounting metal an unite with each 0th to form a mounting co metals commo joint between more correctly since other may be equally suitable as throughout to my process as although operation,

union between be termed a metals mit their use the strains of and will also permit without danger of the ordinary drawthe use of heretofore were enfor that purpose when due to their tendwith my invention .the mounting die in such a manner d the alloy of the die actually er at their contacting surfaces ling a weld. When the that the operations, the the die might brazed union. But

than those used for brazing a mounting, I prefer the specification and claims to refer a true autogenous weld.

Many of the metals or alloys heretofore used for mounting method, properly high elastic limit having a weld with a particular form of welding it will be understood that the the two metals is not necessarily will, under the-conditions of my the die alloy. at high temperatures,

Metals and a coeflicient of expansion higher than the alloy of the steel have die, are especially a copper-nickel alloy such as all been found to be applying the mounting me held in a crucible or other container located and suitable. Bronze, Monel metal, or satisfactory. In tal the die may be Jackson Heights, N. Y., as- Stellite Company, a corpora- 3, 1931, Serial No. 564,711

in a position which will permit the formation about thedie of a mounting having the shape desired. The mounting metal, in the form of solid particles, is then introduced into the refractory container or crucible, along with a suitable flux, and heat is applied to completely melt the metal into place about the die. A mounting metal or alloy is used which has a much lower fusion point than the alloy of the die, so that it may be completely reduced to a molten condition 10 without fusing the die, or in any way altering the size or shape of the die hole. The flux used should be one capable of cleaning the surface of the die, and the temperature should preferably be carried to a point somewhat higher than the 15 melting point of the mounting metal. On cooling the mounting metal shrinks to a much greater extent than the die, which causes a tension to be set up in the mounting. The elasticity of this metal however is sufl'icient to hold this tension 0 until the unit is entirely cold. Thus a die assembly is formed in which the mounting is not only welded to the surface of the die, but also acts to support and reinforce it under tension.

The method has been found to be especially suitable for mounting tungsten alloy dies of the type whose extreme hardness may be attributed to the presence of certain amounts oftungsten carbide. These dies, which will be referred to as tungsten carbide dies, are admirably suited in hardness to resist the frictionaLwear of wire drawing, but they do not have suflicient strength to resist cracking when mounted in the mannerheretofore used. I prefer as a mounting metal for such dies an alloy of substantially the composition, copper nickel 31%, iron 1%, and manganese 3%. The die is placed in a crucible in the manner previously described, and the mounting metal and a borax flux are distributed about the die. The crucible is then placed in a furnace and heated to-a temperature of approximately 1200 C. This temperature is sufiicient thoroughly to fuse the surrounding alloy, whereby the fluid metal fills the unconfined space about the die. The flux acts to clean the surface of the die, and the metal of the mounting welds with this surface, although there appears to be no actual fusion of the die alloy. As previously explained, the mounting cools under tension. This tension, along with the welded contact of the two alloys, so reinforces the die as to permit the use of tungsten carbide dies in drawing operations where heretofore they were of little or no value, due to their tendency to crack.

A typical form of the invention is shown in the drawing, in which Figures 1 and 2 representtwo stages in the process of mounting an alloy die, and

Figure 3 is a mounted die.

Referring to Figure 1, a graphite crucible It may be used as the refractory container. Within the crucible It may be placed a removable graphite block H having a centrally located point or projection to aid in centering the die. A dieblank l2, provided with a centering-hole or depression, is placed on the block ll, flux and pieces of metal are placed in the crucible, and the whole then placed in a furnace to fuse the said metal.

Upon removal from the furnace, the die is found to be surrounded with metal i3, as shown in Figure 2. The contents of the crucible it are then allowed to cool, and when cool are removed from the crucible. The mounting metal I: is

then turned down to the desired shape and size,

and the die I 2 is drilled.

In Figure 3, the drilled die I! is shownsurrounded by the turned mounting metal l3.

Although especially applicable to tungsten carbid dies, the invention may also be useful in mounting many other types of dies which have extreme hardness, but which must be reinforced by means of a mounting. Various modifications in the particular procedure described may also be made without departing from the spirit of my invention, especially with reference to the manner of placing and fusing the mounting metal to form the shape desired. For example the, mounting metal or alloy ,may be melted about the die, and welded thereto by means of an ordinary welding flame or torch while supported inmost any type of a suitable container. The invention should not be limited other than as defined in the appended claims.

I claim:

1. A method of mounting alloy dies which comprises placing the die in a refractory container, disposing about said die solid particles of a mounting composition consisting chiefly of copper and nickel and having a higher coeflicient of expansion and a higher elastic limit at high tempera- 5 tures than the alloy of the die, adding thereto a flux adapted to clean the surface of the die, and heating the container to a temperature such that the mounting composition is completely fused and welding occurs at the contacting surfaces of the die and the mounting, whereby the die is securely I bonded to the mounting and re-enforced by the effect of the high elastic tension which is set up in the mounting, and breaking of the die when in use is minimized. 2. A method of mounting tungsten carbide dies which comprises placing the die in a refractory container, disposing about said die a mounting composition comprising copper, nickel, iron and manganese, said composition having a higher elastic limit at high temperatures, a higher coefficient of expansion, and a lower melting point than said die material, adding thereto a flux adapted to clean the surface of the die, and heating the container to a temperature such that the mounting composition is completely fused and welding occurs at the contacting surfaces of the die and the mounting, whereby during cooling of the mounting the elasticity thereof is suflicient to withstand the tension created by the unequal contraction of the die and the die mounting, and fracturing of the die when in use is minimized.

3. A method of mounting tungsten carbide dies which comprises placing the die in a refractory container, disposing about said die a mounting metal having substantially the composition, copper 65%, nickel 31%, iron 1%, and manganese 3%, adding. thereto a borax flux, and heating the container to a temperature of about 1200" (2., whereby the mounting metal welds with the surface of the die.

WIILIAM A. WISSLER. 

